计算下面各题,能简算的请用简便方法计算.

1个回答

  • 解题思路:(1)根据加法交换律进行计算;

    (2)根据加法交换律进行计算;

    (3)根据加法交换律进行计算;

    (4)根据加法交换律和结合律以及连减的性质进行计算;

    (5)按照从左向右的顺序进行计算;

    (6)按照从左向右的顺序进行计算;

    (7)根据连减的性质进行计算;

    (8)根据加法交换律和结合律进行计算.

    (1)8.38+9.43+6.62,

    =8.38+6.62+9.43,

    =15+9.43,

    =24.93;

    (2)5.86-1.77+2.54,

    =5.86+2.54-1.77,

    =8.4-1.77,

    =6.63;

    (3)47.2+8.6-7.2,

    =47.2-7.2+8.6,

    =40+8.6,

    =48.6;

    (4)28.6-3.8-14.6-6.2,

    =(28.6-14.6)-(3.8+6.2),

    =14-10,

    =4;

    (5)8-2.6-1.77,

    =5.4-1.77,

    =3.63;

    (6)7.4+0.93-4.36,

    =8.33-4.36,

    =3.97;

    (7)17.34-(9.8+6.34),

    =17.34-9.8-6.34,

    =17.34-6.34-9.8,

    =11-9.8,

    =1.2;

    (8)0.93+5.45+7.07+4.55,

    =(0.93+7.07)+(5.45+4.55),

    =8+10,

    =18.

    点评:

    本题考点: 小数四则混合运算;运算定律与简便运算.

    考点点评: 考查了运算定律与简便运算,四则混合运算.注意运算顺序和运算法则,灵活运用所学的运算律简便计算.